spi: work on fw support for simple spi core

1 files changed, 25 insertions, 77 deletions

diff --git a/firmware/zpu/lib/spi.c b/firmware/zpu/lib/spi.c
index af0d8a68f..de3645fe3 100644
--- a/firmware/zpu/lib/spi.c
+++ b/firmware/zpu/lib/spi.c
@@ -1,4 +1,5 @@
 /*
+ * Copyright 2012 Ettus Research LLC
  * Copyright 2007,2008 Free Software Foundation, Inc.
  *
  * This program is free software: you can redistribute it and/or modify
@@ -17,94 +18,41 @@
 
 #include "spi.h"
 #include "memory_map.h"
-#include "pic.h"
 #include "nonstdio.h"
+#include "mdelay.h"
 
-//void (*volatile spi_callback)(void); //SPI callback when xfer complete.
-
-//static void spi_irq_handler(unsigned irq);
-
-void
-spi_init(void) 
+void spi_init(void)
 {
-  /*
-   * f_sclk = f_wb / ((div + 1) * 2)
-   */
-  spi_regs->div = 1;  // 0 = Div by 2 (25 MHz); 1 = Div-by-4 (12.5 MHz)
+  spi_core->divider = 100;
 }
 
-void
-spi_wait(void) 
+void spi_wait(void)
 {
-  while (spi_regs->ctrl & SPI_CTRL_GO_BSY)
-    ;
+  //assumption that divider is reasonably small
+  mdelay(1);
 }
 
-uint32_t
-spi_transact(bool readback, int slave, uint32_t data, int length, uint32_t flags) 
+uint32_t spi_transact(bool readback, int slave, uint32_t data, int length, uint32_t flags)
 {
-  flags &= (SPI_CTRL_TXNEG | SPI_CTRL_RXNEG);
-  int ctrl = SPI_CTRL_ASS | (SPI_CTRL_CHAR_LEN_MASK & length) | flags;
-
-  spi_wait();
-
-  // Tell it which SPI slave device to access
-  spi_regs->ss = slave & 0xffff;
-
-  // Data we will send
-  spi_regs->txrx0 = data;
+    uint32_t control_word = 0;
+    control_word |= (slave << SPI_CORE_SLAVE_SELECT_SHIFT);
+    control_word |= (length << SPI_CORE_NUM_BITS_SHIFT);
+    if ((flags & SPI_PUSH_RISE)  != 0) control_word |= (1 << SPI_CORE_DATA_IN_EDGE_SHIFT);
+    if ((flags & SPI_PUSH_FALL)  != 0) control_word |= (0 << SPI_CORE_DATA_IN_EDGE_SHIFT);
+    if ((flags & SPI_LATCH_RISE) != 0) control_word |= (1 << SPI_CORE_DATA_OUT_EDGE_SHIFT);
+    if ((flags & SPI_LATCH_FALL) != 0) control_word |= (0 << SPI_CORE_DATA_OUT_EDGE_SHIFT);
+
+    uint32_t data_out_rev = 0;
+    for (size_t i = 0; i < length; i++){
+        const int bit = ((data >> i) & 0x1);
+        data_out_rev |= (bit << (length - i - 1));
+    }
 
-  // Run it -- write once and rewrite with GO set
-  spi_regs->ctrl = ctrl;
-  spi_regs->ctrl = ctrl | SPI_CTRL_GO_BSY;
-
-  if(readback) {
     spi_wait();
-    return spi_regs->txrx0;
-  }
-  else
-    return 0;
-}
-
-/*
-void spi_register_callback(void (*volatile callback)(void)) {
-  spi_callback = callback;
-}
-
-static void spi_irq_handler(unsigned irq) {
-//  printf("SPI IRQ handler\n");
-//  uint32_t wat = spi_regs->ctrl; //read a register just to clear the interrupt
-  //spi_regs->ctrl &= ~SPI_CTRL_IE;
-  if(spi_callback) spi_callback(); //we could just use the PIC to register the user's callback, but this provides the ability to do other things later
-}
-
-uint32_t spi_get_data(void) {
-  return spi_regs->txrx0;
-}
-
-bool 
-spi_async_transact(int slave, uint32_t data, int length, uint32_t flags, void (*volatile callback)(void)) {
-  flags &= (SPI_CTRL_TXNEG | SPI_CTRL_RXNEG);
-  int ctrl = SPI_CTRL_ASS | SPI_CTRL_IE | (SPI_CTRL_CHAR_LEN_MASK & length) | flags;
-
-  if(spi_regs->ctrl & SPI_CTRL_GO_BSY) {
-    printf("Async SPI busy!\n");
-    return false; //we don't wait on busy, we just return failure. we count on the host to not set up another transaction before the last one finishes.
-  }
-
-  // Tell it which SPI slave device to access
-  spi_regs->ss = slave & 0xffff;
-
-  // Data we will send
-  spi_regs->txrx0 = data;
-
-  spi_register_callback(callback);
-  pic_register_handler(IRQ_SPI, spi_irq_handler);
+    spi_core->control = control_word;
+    spi_core->data = data_out_rev;
 
-  // Run it -- write once and rewrite with GO set
-  spi_regs->ctrl = ctrl;
-  spi_regs->ctrl = ctrl | SPI_CTRL_GO_BSY;
+    if (readback) spi_wait();
 
-  return true;
+    return readback_mux->spi;
 }
-*/